<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>10-字符串</title>

</head>
<body>


<script>
    let a = "abc"
    let b = 'abc'
    let c = `abc`

    let money = 90;
    let str = "这件衣服卖" + money + "元"
    let str2 = `这件衣服卖${money}元`
    console.log(str);
    console.log(str2);

</script>


<script>
    let str3 = "abcdef";
    let s = str3.substr(2,3);
    console.log(s);

    let s2 = str3.substring(2,3);
    console.log(s2);

    let s3 = str3.toUpperCase();
    console.log(s3);
</script>

</body>
</html>